Elucidating the effect of heat stress on milk production and composition in Jersey crossbred cows using test day records integrated with NASA POWER satellite data

• Published in: International journal of biometeorology 2024-12, Vol.68 (12), p.2641-2651
• Main Authors: Gayari, Indrajit, Rahman, Mokidur, Lalhmingmawii, Sylvia, Mandal, Ajoy
• Format: Article
• Language: English
• Subjects: Animal Physiology; Animals; Biological and Medical Physics; Biophysics; Cattle; Cattle - genetics; Cattle - physiology; Composition effects; Cow's milk; Dependent variables; Earth and Environmental Science; Environment; Environmental effects; Environmental Health; Fats - analysis; Female; Genetic diversity; Heat stress; Heat Stress Disorders - veterinary; Heat tolerance; Heat-Shock Response; Hot Temperature - adverse effects; Humidity; Humidity indexes; India; Lactation; Meteorological data; Meteorology; Milk; Milk - chemistry; Milk - metabolism; Milk production; Milk Proteins - analysis; Original Paper; Plant Physiology; Proteins; Regression models; Satellite data; Temperature effects; United States; United States National Aeronautics and Space Administration
• ISSN: 0020-7128; 1432-1254; 1432-1254
• DOI: 10.1007/s00484-024-02774-7

The present study was undertaken to determine the effect of heat stress on milk production (test day milk yield) and compositional traits (fat%, protein%, fat yield, protein yield) as well as to observe the pattern of response to increasing heat load on these traits in Jersey crossbred cows, maintained at ICAR-National Dairy Research Institute, Eastern Regional Station, Kalyani, West Bengal, India. The weather information, obtained from the NASA POWER database based on the location of the farm latitude and longitude, was used to calculate the Temperature Humidity Index (THI). To analyze the data, a linear model was fitted to the milk production and compositional records, which were adjusted for additive genetic effect of animal, permanent environmental effect of animals and known environmental sources of variations. Subsequently, a segmented linear regression model was fitted, and the least squares estimates of production and composition traits in different classes of THI were used as the dependent variable. Two THI break-points (BP) for milk yield and one THI BP for fat yield, protein %, and protein yield were found. The first and second BP for milk yield was at THI 59 and 77, respectively, with a significant decline in milk yield of -0.04 kg/unit of THI at second BP. The BP for fat and protein yield was at THI 76, with a decline rate of -1.18 and − 0.61 g/unit of THI increase, respectively. The findings revealed the significant adverse effects of THI on milk production and composition traits in Jersey crossbred cattle.